Think about the shape of a heart.
Now, divide it in half, right down the middle. You realize that the right side creates a question mark. And that's a perfect symbol for what happens when a relationship is fractured, if not completely broken: questions, of what happened, of what the other half is thinking or feeling, of what could have been. A broken heart represents insecurity, because it opens endless questions and exposes the heart to an open side where there had been none before. </3
Now, think about the heart as a complete whole. The majority of the surface area is facing upwards, towards the light of the sky and if I may say towards God. On the contrary, the bottom of the heart slims to a sharp point, almost as if meant to be a weapon towards the devil underneath and below, exposing the least amount of surface area possible. And most critically, the heart is a complete whole, with each side protecting the other from what would otherwise be outside elements if they were not facing each other in embrace. <3
"Keep vigilant watch over your heart;
that's where life starts." -- Proverbs 4:23